山本 博徳

Lipophilic hormones of steroidal origin such as the sex hormones and 1,25-dihydroxy vitamin D-3 (1,25[OH](2)D-3) function by regulating patterns of gene expression in cells. The mediators of such actions are nuclear receptors that recognize these ligands with high affinity and selectivity and function through several mechanisms as gene specific transcription factors. As a result of the mechanistic complexity of nuclear receptor action, recent studies have revealed that both synthetic analogs as well as novel mimetics of a receptor's natural hormonal ligand are capable of modulating functional responses in both cell- and gene-selective manners. These findings have given rise to the term selective receptor modulators, typified by such synthetic estrogen receptor ligands as tamoxifen and raloxifene. A number of vitamin D analogs have been prepared that appear to exhibit tissue-selective activity-most notable through their inability to induce levels of hypercalcemia typical of the activity of the natural hormone 1,25(OH)(2)D-3. Because this debilitating yet normal feature of the natural ligand limits its usefulness in a variety of clinical indications, including its application to prevent bone disease caused by secondary hyperparathyroidism, this feature of many of the new analogs is especially welcome. This article discusses what constitutes a selective receptor modulator and whether the current vitamin D analogs represent such entities. (C) 2002 by the National Kidney Foundation, Inc.

Our aim was to understand the mechanism of immunological changes associated with the use of an adsorptive-type extracorporeal device (Adacolumn) that has been developed for selective adsorption of granulocytes and monocytes/macrophages from peripheral blood of patients with active ulcerative colitis. The column is filled with carriers (G-1 beads) that have a diameter of 2 mm and are made of cellulose diacetate. In peripheral blood treated with the G-1 beads or peripheral blood from patients with active ulcerative colitis following granulocyte and monocyte adsorption apheresis, a significant suppression of proinflammatory cytokines (tissue necrosis factor-alpha, interleukin-1beta, interleukin-6, and interleukin-8) production by leukocytes, neutrophil chemotaxis, down-regulation of leukocyte adhesion molecule (L-selectin) and neutrophil adhesion to interleukin-1beta-activated endothelial cells were observed. Furthermore, after granulocyte adsorption therapy, the number of CD10-negative premature granulocytes increased, indicating increased turnover of these cells in the circulation. Our observations suggest that selective granulocyte and monocyte adsorption is associated with modified peripheral blood leukocyte function favorable to patients with ulcerative colitis and possibly other autoimmune disorders which reflect leukocyte hyperactivity.

The awareness of phosphorus intake is important because hyperphosphatemia and hypophosphatemia both impair bone metabolism. Phosphorus consumption from food was obtained from values in the Food Balance Sheet (FBS) of Japan from 19 60 to 1995. The amounts of phosphorus calculated from the FBS increased gradually from 1,243 mg/d in 1960 to 1,332 mg/d in 1975 and to 1,421 mg/d in 1995. This is explained by the increased consumption of cow's milk and milk products, meat, and chicken eggs. The main foods supplying phosphorus in 1995 were cereals, milk and milk products, fishes and shellfishes, and vegetables; their contributions were 24.4, 15.8, 14.2, and 10.9%, respectively. The phosphorus-to-calcium ratio calculated from the FBS was 3.5.1. in 1960, which decreased to 2.89 in 1975 and 2.44 in 1995. Therefore total phosphorus consumption in 1995 was presumably more than 1,500 mg/d when imported food containing phosphorus and the consumption of phosphorus-containing food additives in Japan are also considered. These findings suggest that the phosphorus consumption estimated from the FBS is increasing and that more attention should be paid to the maintenance of healthy bones in Japan, where the average amount of calcium intake is less than 600 mg/d.

Background: Deep insertion of an enteroscope by use of a push technique is difficult. A new method of enteroscopy was developed, a double-balloon method, to improve the access to the small intestine. Methods:The new method uses 2 balloons, one attached to the tip of the endoscope and another at the distal end of an overtube. By using these balloons to grip the intestinal wall, the endoscope can be inserted further without forming redundant loops in the small intestine. This method was tried with a standard upper endoscope in 3 patients and with a longer enteroscope in 1 patient. Results: Despite its short length the upper endoscope was successfully inserted as far as 30 to 50 cm beyond the ligament of Treitz in the 3 patients. In the fourth patient the longer enteroscope was successfully inserted beyond the ileo-cecal valve. Conclusions: The double-balloon method facilitates endoscopic access to the small intestine.